Triplet-excited-state-involved photonic and electronic properties have attracted tremendous attention for next-generation technologies. To populate triplet states, facile intersystem crossing (ISC) for efficient exciton spin-flipping is crucial, but it remains challenging in organic molecules free of heavy atoms. Here, a new strategy is proposed to enhance the ISC of purely organic optoelectronic molecules using heteroatom-mediated resonance structures capable of promoting spin-flipping at large singlet-triplet splitting energies with the aid of the fluctuation of the state energy and n-orbital component upon self-adaptive resonance variation. Combined experimental and theoretical investigations confirm the key contributions of the resonance variation to the profoundly promoted spin-flipping with ISC rate up to ≈10 s in the rationally designed NPX (X = O or S) resonance molecules. Importantly, efficient organic ultralong room-temperature phosphorescence (OURTP) with simultaneously elongated lifetime and improved efficiency results overcoming the intrinsic competition between the OURTP lifetime and efficiency. With the spectacular resonance-activated OURTP molecules, time-resolved and color-coded quick response code devices with multiple information encryptions are realized, demonstrating the fundamental significance of this approach in boosting ISC dynamically for advanced optoelectronic applications.

The interfacial instability of the lithium-metal anode and shuttling of lithium polysulfides in lithium-sulfur (Li-S) batteries hinder the commercial application. Herein, we report a bifunctional electrolyte additive, i.e., 1,3,5-benzenetrithiol (BTT), which is used to construct solid-electrolyte interfaces (SEIs) on both electrodes from in situ organothiol transformation. BTT reacts with lithium metal to form lithium 1,3,5-benzenetrithiolate depositing on the anode surface, enabling reversible lithium deposition/stripping. BTT also reacts with sulfur to form an oligomer/polymer SEI covering the cathode surface, reducing the dissolution and shuttling of lithium polysulfides. The Li–S cell with BTT delivers a specific discharge capacity of 1,239 mAh g−1 (based on sulfur), and high cycling stability of over 300 cycles at 1C rate. A Li–S pouch cell with BTT is also evaluated to prove the concept. This study constructs an ingenious interface reaction based on bond chemistry, aiming to solve the inherent problems of Li–S batteries.

Highlights d Small molecules form a covalent bond with palmitate cysteine d Covalent engagement of cysteine inhibited TEAD4,Yap1 protein-protein interaction d Inhibition of TEAD4,Yap1 in mammalian cells blocked TEAD transcriptional activity d Small-molecule inhibition of TEAD4,Yap1 inhibited glioblastoma cell viability

The exciton dissociations and charge recombinations to a triplet state in the donor−acceptor heterojunction solar cells of [2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta-[2,1-b;3,4-b]dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT) blended with ten different fullerene derivatives are theoretically investigated by using electronic structure calculations together with a Marcus formula. The detailed discussions of available accuracy in the evaluation of all quantities entering the rate expression (driving force, electronic coupling, and internal and external reorganization energies) are provided. The results reveal that the exciton dissociations in most blends are barrierless reactions because the corresponding values of driving forces and reorganization energies are very close; however, the recombinations from the charge transfer states to the triplet state of PCPDTBT occur in the Marcus normal regime. The predicted rates for both the exciton dissociation and charge recombination are in quite good agreement with experimental measurements. In addition, as the triplet charge transfer states are formed, their recombination rates become two orders larger than those for the singlet ones and have orders similar to the exciton dissociations. It is thus expected that the triplet charge recombinations are dominant channels, whereas the singlet charge recombinations can be safely neglected because of quite small rates compared to exciton dissociation ones.

Auxetic materials possess special applications due to their unique negative Poisson’s ratios (NPRs). As a classic 2D carbon material, the NPR of graphene is still deliberated. Introducing the NPR in graphene would increase its extraordinary properties, and the NPR together with other properties would bring more significant applications for graphene. In this Letter, on the basis of first-principles calculations, we reconfigure the structure of graphene, and, as an example, we propose a new 2D planar carbon allotrope, xgraphene, which is constructed by 5–6–7 carbon rings. Our theoretical calculations indicate that xgraphene has an NPR and constitutes a broad spectrum of metal ion battery anodes with high performance. Its maximum storage capacities are 930/1302/744/1488 mAh/g for Li/Na/K/Ca-ion batteries. It has low metal-ion diffusion energy barriers (≤0.49 eV) and low average open-circuit voltages (≤0.53 V). Our density functional theory results also showed that it is intrinsically metallic and possesses dynamic, thermal, and mechanical stabilities. Its intrinsic NPR, which stems from the weakness of coupling of carbon–carbon bonds, is found upon loading the uniaxial strain along the armchair direction. This work not only opens up a new direction for the design of the next-generation broad-spectrum energy-storage materials with low cost and high performance but also offers a class application for auxetic materials.

Among five methods in predicting intersystem crossing of TADF molecules, NTO similarity and n-orbital analyses based on the T1 structure were found to be efficient with low computational costs and high accuracy.

Ratiometric luminescent oxygen sensing based on dual fluorescence and phosphorescence emission in a single matrix is highly desirable, yet the designed synthesis remains challenging. Silver-chalcogenolate-cluster-based metal-organic frameworks that combine the advantages of silver clusters and metal-organic frameworks have displayed unique luminescent properties. Herein, we rationally introduce −NH 2 groups on the linkers of a silver-chalcogenolatecluster-based metal-organic framework (Ag 12 bpy-NH 2) to tune the intersystem crossing, achieving a dual fluorescence-phosphorescence emission from the same linker chromophore. The blue fluorescence component has a 100-nm gap in wavelength and 8,500,000-fold difference in lifetime relative to a yellow phosphorescence component. Ag 12 bpy-NH 2 quantifies oxygen during hypoxia with the limit of detection of as low as 0.1 ppm and 0.3 s response time, which is visualized by the naked eye. Our work shows that metal clusterbased MOFs have great potential in luminescent sensing, and the longer-lived chargeseparated states could find more photofunctional applications in solar energy transformation and photocatalysis.

We report a new class of polyphenyl polysulfides synthesized by condensation reactions between 4,4′-thiobisbenzenethiol (TBBT) and sulfur with four different molar ratios in a toluene/carbon disulfide mixture at room temperature.